Another thing I like is that even when a spell you cast is countered, prowess is not connected to said, so you will still get a +1/+1 boost!
her abilities allow her to make a "stash" of events at the beginning of the game, and either quickly draw them, or copy via her signatures, but she has only 3 copies of "Painted World" (each working once per game) and has no means to put extra cards beneath her sheet, so this advantage would run out eventually, making her no different than other investigators in how she plays the cards
Since Pokemon had just been released, so much wasn't finalized yet and the series as a whole had yet to settle on its style
Although activating the Tome is quite expensive, apparently Brian Weissman thought it was still good enough in this deck filled with Power Nine and other insanely strong cards from the early days of Magic, like Card not found and Card not found
Being able to stall indefinitely so long as you continued attaching a Psychic energy was a viable strategy in the TCGs early days, and Mewtwo was one of the main ways to grind out wins that way